Re: [Qemu-devel] [PATCH 14/17] main-loop: use GSource to poll AIO file descriptors

[Anthony Liguori <anthony@codemonkey.ws>]

Paolo Bonzini <pbonzini@redhat.com> writes:

> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  main-loop.c | 23 ++++++-----------------
>  main-loop.h |  2 --
>  2 file modificati, 6 inserzioni(+), 19 rimozioni(-)
>
> diff --git a/main-loop.c b/main-loop.c
> index b290c79..209f699 100644
> --- a/main-loop.c
> +++ b/main-loop.c
> @@ -205,6 +205,7 @@ static AioContext *qemu_aio_context;
>  int main_loop_init(void)
>  {
>      int ret;
> +    GSource *src;
>  
>      qemu_mutex_lock_iothread();
>      ret = qemu_signal_init();
> @@ -219,6 +220,9 @@ int main_loop_init(void)
>      }
>  
>      qemu_aio_context = aio_context_new();
> +    src = aio_get_g_source(qemu_aio_context);
> +    g_source_attach(src, NULL);
> +    g_source_unref(src);
>      return 0;
>  }
>  
> @@ -481,8 +485,6 @@ int main_loop_wait(int nonblocking)
>  
>      if (nonblocking) {
>          timeout = 0;
> -    } else {
> -        aio_bh_update_timeout(qemu_aio_context, &timeout);
>      }
>  
>      /* poll any events */
> @@ -505,10 +507,6 @@ int main_loop_wait(int nonblocking)
>  
>      qemu_run_all_timers();
>  
> -    /* Check bottom-halves last in case any of the earlier events triggered
> -       them.  */
> -    qemu_bh_poll();
> -

This is an awesome cleanup!

What do you think about deprecating bottom halves in the !block code in
favor of idle functions?  I don't see any reason to keep using bottom
halves...

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>

Regards,

Anthony Liguori

>      return ret;
>  }
>  
> @@ -519,11 +517,6 @@ QEMUBH *qemu_bh_new(QEMUBHFunc *cb, void *opaque)
>      return aio_bh_new(qemu_aio_context, cb, opaque);
>  }
>  
> -int qemu_bh_poll(void)
> -{
> -    return aio_bh_poll(qemu_aio_context);
> -}
> -
>  void qemu_aio_flush(void)
>  {
>      aio_flush(qemu_aio_context);
> @@ -543,16 +536,12 @@ void qemu_aio_set_fd_handler(int fd,
>  {
>      aio_set_fd_handler(qemu_aio_context, fd, io_read, io_write, io_flush,
>                         opaque);
> -
> -    qemu_set_fd_handler2(fd, NULL, io_read, io_write, opaque);
>  }
> +#endif
>  
>  void qemu_aio_set_event_notifier(EventNotifier *notifier,
>                                   EventNotifierHandler *io_read,
>                                   AioFlushEventNotifierHandler *io_flush)
>  {
> -    qemu_aio_set_fd_handler(event_notifier_get_fd(notifier),
> -                            (IOHandler *)io_read, NULL,
> -                            (AioFlushHandler *)io_flush, notifier);
> +    aio_set_event_notifier(qemu_aio_context, notifier, io_read, io_flush);
>  }
> -#endif
> diff --git a/main-loop.h b/main-loop.h
> index 47644ce..c58f38b 100644
> --- a/main-loop.h
> +++ b/main-loop.h
> @@ -312,7 +312,5 @@ void qemu_iohandler_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds, int rc
>  
>  QEMUBH *qemu_bh_new(QEMUBHFunc *cb, void *opaque);
>  void qemu_bh_schedule_idle(QEMUBH *bh);
> -int qemu_bh_poll(void);
> -void qemu_bh_update_timeout(uint32_t *timeout);
>  
>  #endif
> -- 
> 1.7.12